1. Field of the Invention
The present invention relates to an axial through flow motor pump with an incorporated flowmeter and pressure controller.
The invention is particularly adapted to equip automatic coffee machines, but it can be used for numerous other applications requiring pressurized liquid supply from a reservoir.
2. Discussion of Background Information
The French Patent No. FR 98 06 431 filed by the Applicant of the present invention describes a coffee machine comprising a motor pump associated with a pressure controller mounted on the supply circuit and making it possible not only to control the water supply system, but also to remove the reservoir to fill it up due to the fact that the pressure controller is constituted of two elements that can be coupled, one of which is fixed on the frame of the machine and the other to the base of the reservoir, each of these two elements being automatically sealed when they are separated.
The fixed element is connected to the motor pump and is equipped with a flexible membrane acting on an electric contact as a function of the variations in pressure generated by the modifications of the water level in the reservoir. The liquid that penetrates into this element converges to a single chamber in which the flexible membrane and the outlet orifice toward the motor pump are located. Under certain conditions, this arrangement causes an aberrant functioning of the electric contact, in particular during stops and starts of the motor pump.